Sparks was last seen on Oct. 1, 2011 at 1 p.m. at St. John and Denver avenues at 1 p.m. Her body was found on Oct. 4, 2011 at Northeast 120th Street just east of North Eastern Avenue.

Niemeier said Reed was last seen on Aug. 20 at 1 a.m. in 5600 to 5700 block of St. John Avenue. Her body was found on Aug. 21 at 6:30 a.m. at 134th and Scott in Kearney.

Police said there is possibly one living victim. They believe there are other living victims out there and want to hear from them.

Investigators said they have developed a description of a vehicle they are looking for in connection with the case. It's an American-made late '70s to early '90s model white pickup truck with an off-color passenger door.

Niemeier said it may be blue or green.

Investigators also showed off a size 11 canvas-style shoe that was found in the area where Sparks' body was found.

Police described it as a well-worn shoe that was first available in the United States in April 2010.

Authorities said the victims were prostitutes.

"It doesn't matter what kind of lifestyle someone leads -- high-risk lifestyle or otherwise -- they're a victim, and it doesn't give anyone the right to take their life," Niemeier said.

Investigators said they are focusing investigation on Caldwell, Clay, Clinton and DeKalb counties and up the Interstate 35 corridor.

Niemeier said it was very important that people living in those counties were in tune with the investigation.

"Because these are the people we want looking for the truck," Niemeier said.

Anyone with information is asked to call the TIPS Hotline at 816-474-TIPS.